Damm, the adress given returns 503 Service Temporarily Unavailable.

I did a litte investigation, and found the possibility to return 444 in Nginx, to let them loose time. More or less a 404, but without notification to the client, so the connection stays open, until timeout. Maybe that is also an idea. I think everybody should waste more time and resources of spammers. If you use OpenBSD with OpenSMTPd as Mailserver, there is a tarpit included to keep connections for spamers open. We should do this everywhere we can.